Work Vehicle Access Monitoring and Control System

ABSTRACT

An access control system for a work vehicle that has an engine and a location is provided, the system including location sensor that indicates the vehicle&#39;s location and an electronic control unit coupled to the sensor that receives the location signal and selectively disables the engine based upon the vehicle&#39;s position outside job site boundary&#39;s or based upon the time of operation at a plurality of job sites, each job site having its own time of operation.

This divisional application claims priority under 35 U.S.C. §120 fromco-pending U.S. patent application Ser. No. 11/534,922 filed on Sep. 25,2006 by M. Javaid Arshad, Zakaria I. Saleh, Prasenjit Adhikari andMichael A. McSweeney with the same title, the full disclosure of whichis hereby incorporated by reference.

FIELD OF THE INVENTION

The invention relates generally to systems for monitoring andcontrolling work vehicles.

BACKGROUND OF THE INVENTION

Computer-based fleet management systems permit operators of largefleets, such as construction and agricultural vehicles, taxicabs, rentalcars, rental trucks, and work vehicles, to monitor the location of, andcontrol access to, those vehicles.

Access to the vehicles is typically controlled using some combination ofvehicle location, typically provided by the GPS receiver, and a codedoperator input device that can be manipulated to communicate with thecomputer controlling the system. An operator is typically provided witha key or other pass card that gives him full and complete access to thevehicle over whatever range he wishes to drive it. The operator eitherhas complete access and control, or none. Such systems, however, do notprovide the flexibility needed by those operating vehicles in theconstruction business.

U.S. Pat. No. 5,532,690, for example, discloses a basic geofencingsystem in which an engine kill switch operates to shutdown the vehicleengine when it leaves a predetermined area. One problem with thisarrangement is that the vehicle, when shutdown, is disabled for allfurther movement. For work vehicles, a sudden irremediable disabling isa problem. For example, the vehicles can block paths or roads. They canprevent the delivery of other materials. If they are disabled from allmovement, they may prevent access by other vehicles, and thereforeprevent other work from being done at the work site.

U.S. Pat. No. 6,249,215, describes a system that provides for gradualreduction in vehicle power when driven outside a predetermined region,but shuts down the vehicle only in predetermined areas. As the vehiclereturns to the original area, the power is gradually restored. Thesystem provides for “safe” shutdown in which the vehicle engine is shutdown only when it travels to a “safe” shutdown site, such as a gasstation. Nothing prevents the vehicle from being driven indefinitely,albeit at a reduced power level.

US patent publication 2003/60938 discloses a vehicle geofencing system.The system includes an electronic controller located inside a vehiclethat dynamically changes the boundaries of its geofence when commandedby a central computer. The system, however, does not control access tothe vehicle, it only controls the frequency with which the vehiclereports to a home base.

Similarly, US patent publication 2002/77750 is directed to a system formonitoring the operation of concrete mixing trucks as they travel to andfrom various job sites. As the vehicles travel, they cross variousboundaries and transmit messages to a home base. The system does notdisable the vehicle when boundaries are crossed.

U.S. Pat. No. 6,204,772 discloses a system for remotely configuring awork vehicle to transmit status information to a remote computer, suchas whether it is operating in a particular region. The system does notdisable the vehicle.

None of the systems described in these references are suited tocontrolling the operation of work vehicles such as those used on jobsites.

What is needed is an access control system for construction workvehicles that controls and monitors the operation of the vehicles in thetypical construction environment, and that will accommodate multiple jobsites. What is also needed is a theft control system for a work vehiclethat shuts the vehicle engine down whenever it travels outside theboundaries of one of the job sites. What is also needed is a theftcontrol system that permits the operator to restart the engine after ashort interval. What is also needed is a system that prevents thevehicle from traveling between job sites. What is also needed is anelapsed time recording system for a work vehicle that monitors the timespent at each job site, both the vehicle's actual presence at each jobsite and the vehicle's operating time at each job site. It is an objectof this invention to provide such a system and method in which thesebenefits are provided by at least one mode of operation.

SUMMARY OF THE INVENTION

In accordance with a first aspect of the invention, an access controlsystem for a work vehicle including an engine is provided, including alocation sensor on the vehicle configured to provide a location signalindicative of the vehicle's location; an electronic control unit coupledto the location sensor to receive the location signal, the control unitfurther including an electronic memory configured to store a pluralityof non-contiguous job sites, wherein the control unit is configured topermit operation of the vehicle within the non-contiguous job sites andto disable the vehicle when the vehicle leaves the non-contiguous jobsites.

The electronic control unit may be configured to shut down the enginewhen the vehicle leaves the job sites. The electronic control unit maybe configurable to prevent the vehicle from being driven from one of theplurality of job sites to another of the plurality of job sites. Theelectronic memory may store a boundary for each of the plurality ofnon-contiguous job sites.

In accordance with a second aspect of the invention, a theft protectionsystem for a work vehicle including an engine is provided, including alocation sensor on the vehicle configured to provide a location signalindicative of the vehicle's location; and an electronic control unitcoupled to the location sensor to receive the location signal, thecontrol unit further including an electronic memory configured to storeboundaries of at least one job site, wherein the control unit isconfigured to shut down the vehicle engine when it leaves theboundaries, and to permit the vehicle engine to be restarted only aftera predetermined interval of time.

The electronic control unit may be configured to permit the engine torun for only a predetermined period of time after being restarted. Theelectronic control unit may be configured to permit the engine to therestarted a predetermined number of times. The electronic control unitmay be configured to prevent restarts after having been restarted thepredetermined number of times. The electronic control unit may beconfigured to permit the engine to continue running upon restart for aslong as it is steered back toward the boundaries, and to shut down theengine after restart if it turns away from the boundaries.

In accordance with a third aspect of the invention, an elapsed timerecording system for a work vehicle including an engine is provided,including a location sensor on the vehicle configured to provide alocation signal indicative of the vehicle's location; and an electroniccontrol unit coupled to the location sensor to receive the locationsignal, the control unit further including an electronic memoryconfigured to store the boundaries of a first job site and a firsttiming counter associated with the first job site, and to store theboundaries of the second job site and a second timing counter associatedwith the second job site.

The location sensor may include a GPS receiver. The electronic controlunit may store in the first timing counter a value indicative of theamount of time the vehicle was located at the first job site, andwherein the electronic control unit may store in the second timingcounter a value indicative of the amount of time the vehicle was locatedat the second job site. The electronic control unit may store in thefirst timing counter a value indicative of the vehicle's running time atthe first job site, and wherein the electronic control unit may store inthe second timing counter a value indicative of the vehicle's runningtime at the second job site. The electronic control unit may beconfigured to receive a definition of an additional job site from onecircuit selected from a group including a long-range wirelesscommunications circuit, a short-range wireless communications circuit,and a wired computer communications circuit. The long-range wirelesscommunications circuit may be a circuit selected from a group includinga cellular telephone and a satellite telephone. The short-range wirelesscommunications circuit may be a circuit selected from a group includinga Bluetooth circuit and an 802.11 circuit.

In accordance with a fourth aspect of the invention, an access controlsystem for a work vehicle including an engine is provided, the systemincluding means for providing a location signal indicative of thevehicle's location; and means coupled to the location sensor forreceiving the location signal, the receiving means further includingelectronic means for storing a plurality of non-contiguous job sites,and further including means for permitting the vehicle to operate withinthe non-contiguous job sites and means for disabling the vehicle whenthe vehicle leaves the non-contiguous job sites.

The means for receiving may include means for shutting down the enginewhen the vehicle leaves the job sites. The means for receiving mayinclude means for preventing the vehicle from being driven from one ofthe plurality of job sites to another of the plurality of job sites. Themeans for storing may be configured to store a boundary for each of theplurality of non-contiguous job sites. The system further includes meansfor downloading a job site definition. The means for downloading mayinclude one circuit selected from the group including a long-rangewireless communications circuit, a short-range wireless communicationscircuit, and a wired computer communications circuit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a construction work vehicle, shown here as aloader-backhoe, that has a vehicle control system.

FIG. 2 is a schematic diagram of the vehicle access control system ofthe vehicle of FIG. 1.

FIG. 3 is a schematic diagram showing the construction work vehicle attwo job sites, showing the vehicle disabled outside of a job site, andshowing the vehicle being hauled from one job site to another job site.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIG. 1, a work vehicle, here shown as a loader-backhoe 100,includes a loader attachment 102, a backhoe attachment 104 and a tractor106. The loader attachment 102 and backhoe attachment 104 are pivotallycoupled to tractor 106. Tractor 106 is supported on front wheels 108 andrear wheels 110 for movement over the ground.

Vehicle 100 is configured for construction work. Both the loaderattachment 102 and the backhoe attachment 104 coupled to and supportedby tractor 106 are configured to engage the ground, permitting thevehicle to dig foundations, trench the earth for cables, rip upconcrete, transport sand, dirt, and gravel, and carry constructionmaterials around on a job site. It is this configuration which makes theloader-backhoe particularly suited to working at construction sites. Itshould be understood that the terms “construction vehicle”, “workvehicle” or “construction work vehicle” are not limited toloader-backhoes. A variety of other vehicles including, for example,wheel-loaders, skid steer loaders, trenchers, bulldozers, and graders,among others, are also construction work vehicles.

Tractor 106 includes an engine 112 that drives the vehicle over theground and provides power for the hydraulic cylinders that move theloader and the backhoe. Engine 112 is coupled to a transmission 114,that in turn drives the rear wheels through differential 116. Engine 112is controlled by an electronic governor 118, which includes an ignitioncircuit (when engine 112 is a gas engine) or an injector rack controller(when engine 112 is a diesel engine). Electronic governor 118 is capableof regulating the speed of engine 112 and of turning engine 112 on andoff.

Tractor 106 includes a hydraulic pump 120 that is coupled to engine 112and is driven thereby. Hydraulic pump 120 provides hydraulic fluid tocylinders, including loader arm lift cylinders 122 and loader bucketcylinders 124 of loader attachment 102, as well as boom swing cylinders126, boom cylinder 128, dipper cylinder 130, and backhoe bucket cylinder132 of backhoe attachment 104. These cylinders move the loader bucketand the backhoe bucket permitting them to engage the ground. When engine112 is turned off, the backhoe 102 and loader 104 attachments aredisabled. When engine 112 is turned on, the backhoe and the loaderattachments 102, 104 are enabled.

Tractor 106 also includes a vehicle access control system 134 coupled tothe engine for (1) determining the vehicle's location, (2) disabling theengine (e.g. turning it on and off) based upon the vehicle's location,and (3) responding to signals provided by the engine (e.g. by governor118) that the engine is running; and (4) logging engine hours.

FIG. 2 illustrates vehicle access control system 134 in more detail.System 134 includes (1) an electronic control unit or ECU 135, (2) alocation sensor, here shown as satellite navigation receiver 136, thatis coupled to ECU 135, (3) a long-range wireless communications circuit138 coupled to ECU 135, (4) a short-range wireless communicationscircuit 140 coupled to ECU 135, and (5) a computer communicationscircuit 142 for communicating with other ECUs or controllers on thevehicle as well as digital computers that are brought to the vehicle andconnected to circuit 142.

ECU 135 is a digital microprocessor-based control unit, whosefunctioning controls the operation of the other components 136, 138,140, 142. In the preferred embodiment, shown here, a single ECU iscoupled to all of the communications circuits and the location sensor.

ECU 135 may be coupled to other circuits and sensors in addition to thecircuits shown here. It may also be programmed to perform additionalfunctions not described herein. In an alternative configuration, severalECU's may be interconnected to collectively perform the functionsdescribed herein. In this alternative configuration, each ECU may becoupled to one of the communications circuits and sensor circuit andcoordinate its activities with the other ECU's over a network thatinterconnects these ECU's.

Location sensor 136 provides a signal indicating the location of thevehicle in at least two dimensions (e.g. latitude and longitude, orother similar coordinate system), and thus whether the sensor (and byextension the, the vehicle) is inside or outside of to dimensional jobsite boundaries. Alternatively, sensor 136 can provide a signalindicating the location of the work vehicle in three dimensions. In itspreferred embodiment, sensor 136 is responsive to navigation signalsprovided by satellites and generates a signal indicating the location ofsensor 136 (and hence of vehicle 100). This navigation signal istransmitted to ECU 135, which is configured to determine the location ofthe vehicle based upon the navigation signal.

Long-range wireless communications circuit 138 is configured to providelong-range wireless telecommunications. In its preferred embodiment,circuit 138 communicates with long-range wireless communicationnetworks, such as cellular phone networks 137 or satellite phonenetworks 139. ECU 135 is configured to transmit location data and otherdata to a remote fleet management computer 141 over circuit 138.

Short-range wireless communications circuit 140 is configured to provideshort-range wireless telecommunications. In its preferred embodiment,circuit 140 is configured to communicate with other digital computerslocated within, adjacent to, or nearby the vehicle. Circuit 140 maycomprise such short-range radio communication circuits as Bluetoothdevices, or IEEE 802.11 devices, such as WiFi transceivers.

Computer communications circuit 142 is configured to provide short-rangewired communications. In its preferred embodiment, circuit 142communicates with digital computers or ECU's located within, adjacentto, or nearby the vehicle. Circuit 142 may comprise an Ethernet circuit,Token Ring circuit, AppleTalk circuit, RS-232 or other serialcommunications circuit, parallel communications circuit or other circuitfor digital communications between ECU 135 and other ECU's, controllers,or digital computers that couple thereto by electrical or opticalconductors.

FIG. 2 also illustrates internal details of the components of ECU 135which include a CPU 144, random access (RAM) memory 146, non-volatile(ROM) memory 148, and an I/O circuit 150, which are coupled together bya control/data/address bus 152.

CPU 144 is a digital central processing unit whose operation iscontrolled by digital instructions stored in non-volatile memory 148.Nothing herein should suggest that CPU 144 performs only the functionsdescribed herein. CPU 144 may perform other functions that are notdescribed herein. In an alternative configuration, several CPU's may beinterconnected to collectively perform the functions described herein.Each CPU may have its own memory circuits and I/O circuit, or may sharethese circuits with other CPUs. Furthermore, the ECU 135 may have morethan the one CPU, RAM, ROM and I/O circuit illustrated herein.

CPU 144 executes instructions stored in ROM memory 148. Theseinstructions control the operation of control system 134. This operationis described below in conjunction with FIG. 3 .

RAM memory 146 provides temporary storage space for variables and othercomputational results as system 134 operates. Memory 146 receives andstores data that CPU 144 generates as CPU 144 executes the instructionsstored in non-volatile memory 148.

RAM memory 146 is preferably nonvolatile, capable of storing data evenwhen the operational power normally provided to ECU 135 is turned off.RAM memory 146 holds many numeric values used during the operation ofthe vehicle. In particular, RAM 146 is configured to hold several valuesthat ECU 135 uses to perform the functions described below. RAM 146stores a list of job sites in which vehicle 100 is authorized tooperate. RAM 146 stores the boundaries of these authorized job sites ina form that permits CPU 144 to determine whether vehicle 100 is insideor outside of the job sites' boundaries when ECU 135 given the vehicle'slocation by location sensor 136. Whenever vehicle 100 is authorized tooperate at an additional job site, new job site boundaries aredownloaded and a new job site defined by those boundaries is added tothe job site list. ECU 135 is programmed to download the job site andtheir boundaries from remote fleet management computer 141 over circuit138 or from a computer 143 located adjacent to vehicle 100 andconfigured to communicate with vehicle 100 wirelessly via circuit 140 orvia a conductor coupling computer 143 and circuit 142. RAM 146 alsostores, for each job site, an amount of time that vehicle 100 isauthorized to operate at that job site. RAM 146 (or, alternatively,memory 148) includes memory locations in which ECU 135 records severaldifferent time values indicating, respectively, (1) the amount of timethe vehicle was at the job site, (2) the amount of time the vehicle wasoperating, (3) the amount of time the engine was running, (4) the amountof time the vehicle was moving, and (5) the amount of time the backhoeor loader attachments were moving or otherwise being used. An signalindicating the time the engine is running is provided to ECU 135 bygovernor 118. An indication that the various controls are being operated(and hence of the interval over which they are operated) can be providedby switches coupled to the controls and to ECU 135 to sense theirmanipulation by the operator (and hence sense the use of the hydraulicelements of the vehicle). Vehicle movement can be sensed by switches inthe transmission responsive to gear engagement, that are coupled to ECU135. Alternatively vehicle movement can be determined by ECU 135monitoring changing vehicle position indicated by position sensor 136.

I/O circuit 150 is coupled to sensor 136 and circuits 138, 140, 142 andis configured to provide the signals and data they generated to CPU 144for the CPU for use in performing the operations described herein.

Engine Disabling when Leaving Job Sites

FIG. 3 illustrates the operation of control system 134 of vehicle 100.In FIG. 3, vehicle 100 is shown in four different locations (100A, 100B,100C, and 100D), each location illustrating the vehicle at a differentplace during normal vehicle operation. The discussion below explains howcontrol system 134 operates when vehicle 100 is located at thesedifferent locations.

When vehicle 100 is at first location 100A it is located withinboundaries 156 of a first job site 154. The second location 100B showsvehicle 100 located adjacent to but outside the boundaries 156 of jobsite 154. The third location 100C shows vehicle 100 located on a trailer158, which is in the process of transporting vehicle 100 from first jobsite 154 to a second job site 160 defined by boundaries 162. The fourthlocation, 100D, shows vehicle 100 located within the boundaries 162 ofthe second job site 160.

ECU 135 on vehicle 100 is programmed to continuously (1) determine thelocation of the vehicle by reading location sensor 136, receiving fromit a signal indicative of the vehicle position, and (2) selectivelydisable the vehicle when it travels outside the boundaries of the jobsites as determined by comparing the position signal with the job siteboundaries in ECU memory and shutting own the engine. ECU 135 disablesthe vehicle by shutting down engine 112. Thus, when vehicle 100 is atlocation 100A within the boundaries of the first job site 154, ECU 135permits the vehicle and the engine to operate by not disabling theengine 112.

Vehicle 100 can be driven across boundaries 156 and out of job site 154,to location 100B. When vehicle 100 is driven to this location, ECU 135is configured to (1) determine that the current location of vehicle 100is outside of the boundaries of job site 154, and based upon thisdetermination (2) shut down engine 112, thereby disabling vehicle 100.

Generally speaking, in order to shut down engine 112 and disable vehicle100, control system 134 transmits a signal to engine governor 118(FIG. 1) signaling the governor to disable the ignition (if engine 112is a spark ignition engine) or to reduce the rack position to zero (ifengine 112 is a diesel engine). Alternatively, control system 134 canshut down engine 112 by shutting off the fuel supply (e.g. by disablingthe fuel pump or closing of valve disposed in the fuel line) or shuttingoff the air supply (e.g. by closing a throttle plate or other air valvethat controls the flow of air to engine 112. Control system 134 isconfigured to determine whether engine 112 is running are not. Enginegovernor 118 signals control system 134 that it is running over signallines that couple the two together.

Limited Restarting to Return to Job Site

In the section above, we described how the operator may drive thevehicle outside of either of the job site boundaries 156, 162, and howwhen this happens, ECU 135 is configured to shut down the engine. Onoccasion, however, the operator may unintentionally drive the workvehicle outside of the job site boundaries. In these instances, theoperator will wish to start to vehicle up and return it to the job siteas soon as possible. ECU 135 is configured to permit a limited number ofengine restarts and limited operation. By permitting a limited number ofengine restarts, the operator is given time to drive the vehicle backinto the job site, or (alternatively) to move the vehicle to a moresecure location outside of the job site.

Permitting the vehicle to be restarted, even if only for a limited time,raises the possibility that a thief could repeatedly restart the vehicle100, drive it a short distance before it is disabled, then repeat theprocess until the vehicle is far away. To reduce the chance of thisoccurring, ECU 135 is configured to prevent the vehicle's engine frombeing restarted for a predetermined interval of time, called a “restartdelay interval”. If the operator attempts to start the engine duringthis time interval, ECU 135 prevents the engine from starting. Onlyafter the restart delay interval has passed will ECU 135 enable thevehicle and permit the vehicle to be restarted. The restart delayinterval is preferably 30 seconds long.

Once the restart delay interval has passed, ECU 135 permits the engine112 to be restarted by re-enabling whatever vehicle systems it hadpreviously disabled to prevent restarting. As mentioned above, thesevehicle systems preferably include rack position, air supply, fuelsupply, or ignition.

ECU 135 does not permit the engine to run indefinitely once it isrestarted, however. ECU 135 monitors the location of the vehicle,recognizes that it is still outside the job site, and permits the engineto run for only a second predetermined time interval called a “restartrun interval”. The restart run interval is preferably 30 seconds.

Having restarted a previously disabled vehicle outside the jobsiteboundaries 156, 162, if the operator does not drive the vehicle backwithin the boundaries of the job site within the restart run interval,ECU 135 is programmed to shut down the engine again. Once ECU 135 shutsdown the vehicle a second time, ECU 135 is programmed to repeat thedelay process and again prevent the engine from restarting for anotherrestart delay interval. Once the restart delay interval has passedagain, the operator can again restart the vehicle and again operate itfor another restart run interval.

ECU 135 is configured to repeat this engine-starting and engine-stoppingprocess a predetermined number of times, preferably four, permitting theoperator each time to return the vehicle to within the boundaries of thejob site. Once this starting/stopping process has been repeated thepredetermined number of times, ECU 135 is configured to totally disableengine 112.

ECU 135 maintains an internal counter in memory 146 or 148. Each timethe vehicle is restarted, ECU 135 increments this counter. Beforerestarting the vehicle, ECU checks this counter to see whether thecounter has reached a maximum number of restarts. Whenever ECU 135determines that the counter has reached the maximum number of restarts,the ECU disables the vehicle by preventing any further restarts. Thus,ECU 135 permits only a limited and predetermined number of restarts. Ifthe operator has not returned to within the boundaries of one of the jobsites listed in ECU 135 memory before this limit is reached, the vehiclewill remain disabled and outside the boundaries of the job sites.

Subsequent efforts to restart the engine, for example, by the operatorusing the ignition switch or other standard starting means, will notwork. If the vehicle has been returned to within the job site boundariessometime during the predetermined number of engine restarts, the vehiclewill again operate as normal within the boundaries of the job site. Onlyafter ECU 135 restarts the vehicle the predetermined number of timesoutside the job site boundaries before returning to the job site willthe vehicle be disabled and not restart.

To enable the vehicle again after it has had its maximum restarts, ECU135 is programmed to respond to a special reset signal transmitted to itfrom a computer coupled to the long-range communications circuit 138,the short-range communications circuit 140, or the wired computercommunications circuit 142.

ECU 135 is programmed to receive the reset signal and responsivelyreturn to its original operating mode in which it periodically testswhether it is within one of the plurality of predetermined noncontiguousjob sites.

It should be clear from this description that control system 134 isconfigured to prevent a work vehicle from being driven from one job sitewhere it is enabled to operate to another distant job site where it isalso enabled to operate. Any attempt to drive the vehicle between twononcontiguous job sites would cause the engine to shut down as describedabove. Of course, if the two job sites were immediately adjacent to eachother, or touching each other, the operator would be able to drive fromone job site to another.

In order to move work vehicle 100 from one job site to a distant andnon-contiguous job site, the work vehicle 100 must be towed or carried.It cannot travel under its own power. Since the job sites are not joinedtogether—i.e. not contiguous—there is no way to get from one job site tothe other without the engine automatically shutting down. It is theregion between the two job sites in which control system 134 shuts theengine down. This prevents vehicle 100 from traveling between job sitesunder its own power. A vehicle traveling on a trailer does not travelunder its own power, and therefore does not need to have its enginerunning.

This is the situation indicated by vehicle 100 at location 100C. Atlocation 100C, vehicle 100 is shown loaded on trailer 158 with thetrailer carrying the vehicle from job site 154 to job site 160. In thepreferred process, vehicle 100 is loaded on trailer 158 within theboundaries of first job site 154. Since vehicle 100 is within theconfines of first job site 154 during this loading process, controlsystem 134 permits the engine of the vehicle to operate and permits theoperator to drive vehicle 100 onto trailer 158. Once vehicle 100 is ontrailer 158, the operator turns off engine 112 of vehicle 100 andreadies vehicle 100 for transport.

The operator can then enter the cab of the vehicle 159 that is coupledto and pulls trailer 158 and carries trailer 158 together with vehicle100 across the boundaries 156 of first job site 154.

The operator can tow vehicle 100 on trailer 158 from first job site 154to second job site 160 whether engine 112 of vehicle 100 is running ornot. If engine 112 of vehicle 100 is indeed running when trailer 158leaves the boundaries of the first job site, control system 134 willshut down engine 112 as described above. Since vehicle 100 is already ontrailer 158, however, disabling the vehicle and shutting down engine 112will not prevent vehicle 100 from being carried from one job site toanother and from being restarted inside the new job site boundaries onceit arrives.

Transportation is not limited to the two job sites illustrated in FIG.3. Additional job sites and corresponding boundaries may be recorded inECU 135, such as work sites, maintenance facilities, repair depots,storage lots, or other locations.

Returning to the example of FIG. 3, the operator eventually arrives atsecond job site 160 with trailer 158 and vehicle 100 in tow. Theoperator tows trailer 158 and vehicle 100 until they are within theboundaries 162 of job site 160. Once within the boundaries of the jobsite, vehicle 100 can be started, and will run continuously. It is thendriven off the trailer and operated at job site 160 to perform work.

ECU 135 is configured to determine whether vehicle 100 is at any of aplurality of job sites, and to permit operation only at those job sites.It uses the vehicle's position, which is derived from location sensor136 and the boundaries of each of the plurality of job sites stored inthe electronic memory of ECU 135 to determine where the vehicle is. Whenvehicle 100 is started at the second job site 160, ECU 135 senses thatvehicle 100 is within the boundaries 162 of the second job site 160 andpermits the operator to start and run vehicle 100. ECU 135 is configuredto automatically and periodically check the location of vehicle 100 atthe second job site 160 just as ECU 135 did at its first job site 154.Since both job sites are defined in the memory of control system 134 asauthorized regions of operation, ECU 135 is configured to not disablevehicle 100, but to permit vehicle 100 to operate at the second job siteas well.

If the operator drives vehicle 100 across the boundaries 162 of secondjob site 160 and outside of the job site 160, control system 134 willperform the identical functions it performed at job site 154. It willidentify that vehicle 100 is no longer within the boundaries of any jobsite and will disable vehicle 100 by turning off engine 112.

Self-propelled travel by vehicle 100 between the two job sites istherefore prevented. A vehicle starting at a first job site cannot exitthat job site and travel to a second job site, and a vehicle at thesecond job site cannot exit that job site and travel to the first jobsite. The vehicle is configured to permit operation at both of those jobsites and to prevent it from being driven between the job sites.

Right of Return to Job Site

The control system 134 is configured to permit the operator to return tovehicle to a job site it inadvertently left. It does this by monitoringthe location of the vehicle. As long as vehicle 100 follows a pathcalculated by control system 134 to return to a job site that thevehicle just departed, ECU 135 will not disable the vehicle, but willpermit it to keep operating.

Referring to FIG. 3, if the work vehicle starts at location 100A insidejob site 154, and is driven across boundary 156 until it is outside jobsite 154 at location 100B, ECU 135 will shut down the vehicle's engine.This was described above. After a predetermined time interval, theoperator will be permitted to restart the vehicle, also as describedabove. In this alternative configuration, ECU 135 is configured topermit the vehicle to return to job site 154 from which it immediatelydeparted without disabling the engine after a predetermined timeduration as described above in the Limited Restart section.

Instead, ECU 135 determines the direction of travel of the vehicle andpermits the vehicle to keep operating as long as the vehicle istraveling in a direction back toward job site 154. When the vehicle isrestarted, ECU 135 begins a timer to determine whether the restart runinterval has been exceeded as described above in the Limited Restartsection. In the Right of Return configuration, however, as soon as ECU135 determines that the vehicle is pointing back toward job site 154,ECU 135 stops determining whether the vehicle has exceeded the restartrun interval. Instead, as long as the direction of travel is directedback toward boundary 156 and job site 154, ECU 135 will permit engine112 to continue running. It will not shut down engine 112 after therestart run interval has expired. However, should the operator turnvehicle 100 away from boundary 156, thereby driving the vehicle in adirection that increases the distance between vehicle 100 and job site154, ECU 135 will shut down engine 112.

Time Logging

Another feature of ECU 135 of control system 134 is its ability to keepa running total of the time the vehicle spends on site for each jobsite, a running total of the time the vehicle engine runs on site foreach job site and a running total of the time the vehicle spendsoperating anywhere, and its ability to shut down vehicle 100 when any(or all) of these totals exceed an associated predetermined amount.

For example, ECU 135 is programmed to store in nonvolatile memory 148 apredetermined vehicle time limit for presence at each job site, apredetermined vehicle time limit for engine running at each job site, apredetermined vehicle time limit for vehicle movement at each job site,and a predetermined vehicle time limit for implement operation at eachjob site. Each job site has a corresponding set of these time limits.

ECU 135 is programmed to maintain timers for each of the three runningtotals in nonvolatile memory 148 and to periodically increment thesetimers as appropriate. When vehicle 100 is in job site 154, ECU 135increments a presence timer, and engine running timer, a vehiclemovement timer, and an implement operation timer that are associatedwith job site 154. Similarly, when vehicle 100 is in job site 160, ECU135 increments a presence timer, an engine running timer, a vehiclemovement timer, and an implement operation timer that are associatedwith job site 160.

Further, ECU 135 is programmed to respectively compare the predeterminedtime limits with the timers, and to disable the vehicle if any of thepredetermined time limits are exceeded.

Even further, ECU 135 is configured to disable the vehicle by shuttingthe engine down for exceeding the time limits.

ECU 135 increments the timers based upon its current location. Whenevertractor 100 is in a particular job site, ECU 135 increments the timersassociated with that job site and not the timers associated with theother job sites. ECU 135 increments the timer associated with totalvehicle operating time whenever the vehicle operates, and regardless ofwhere it is operating. Thus, there are both timers specific to operationat each individual job site and a timer associated with operationanywhere.

When the vehicle changes from one job site to another, ECU 135 isconfigured to sense this change in position and to switch to the timersappropriate for that job site, and to periodically update them,typically on the order of once every 10 milliseconds to once every fewminutes. Unlike prior art systems in which a single timer is maintainedthat indicates the total operating time of the vehicle, control system134 maintains multiple timers, each timer being associated with adifferent and non-contiguous area (in this case different job sites).

ECU 135 further includes a timer that includes overall engine runningtime, no matter where vehicle 100 is located. ECU 135 is configured toincrement this timer whenever the vehicle's engine runs, no matter wherethe vehicle is located.

Thus the areas associated with some timers are discrete andnon-contiguous (i.e. timers for different job sites), some timersoverlap each other in area, but are not coextensive in area (i.e. anyjob site engine running timer and the overall engine running timer),some timers are coextensive in area, but not coextensive in time (i.e.the timer indicating the vehicle's presence at a job site A and thetimer indicating the vehicle's engine running time at job site A).

Providing multiple operating times for several different jobsites and anoverall engine running time is particularly beneficial with workvehicles, which may be authorized to work on jobs at several differentjob sites. Construction work vehicles are often shifted between jobsites unexpectedly. Initial construction plans may anticipate that askid steer loader or loader-backhoe (for example) is required at a jobsite at a particular time to do a particular task. These tasks are oftenestimated at a predetermined number of hours, and customers of thebuilder or contractor are charged accordingly. It is often undesirablefor a work vehicle to be used a worksite for more than the predeterminedand bargained-for period of time.

To enforce these time or use limits, control system 134 is configured tomaintain a plurality of time records indicating the permitted use limitsand actual use of vehicle 100 at a plurality of job sites. Using theexample of FIG. 3, for example, vehicle 100 can be programmed with thepermitted amount of time vehicle 100 may operate at both job sites. Inthis manner, the contractor or builder can keep track of the operatinghours of work vehicles at two different job sites for two differentclients, without having to maintain separate sets of books or rely onmanually entered operator records. Further, the operator can contractwith customers for a predetermined amount of time the vehicle can beused and leave the particular date and time at which that use will occuropen for later adjustment.

For example, if a construction company with a backhoe agrees to dig twofoundations for two different customers at two different job sites andnegotiates a different number of total hours for each customer, controlsystem 134 can be configured to keep track of these hours no matter whenthe hours are worked. Using the example of FIG. 3, the owner of vehicle100 can contract to dig a foundation at job site 154 in 20 hours. Theowner of vehicle 100 can also contract to dig a foundation at job site160 in 30 hours. The boundaries of these two job sites and the hoursallotted for each job can be recorded in the nonvolatile memory 148 ofcontrol system 134. With these limits programmed into control system134, vehicle 100 can be moved to job site 154 and the operator cancommence work. ECU 135 monitors location sensor 136 and increments theelapsed engine running time timer in the memory 148 of ECU 135 as thevehicle works. ECU 135 is configured to periodically compare thiselapsed engine running time to the predetermined time limit of 20 hoursallotted for that job which is also stored in memory 148. When vehicle100 is worked for the agreed-upon and programmed with 20 hours, ECU 135is configured to shut down engine 112 of vehicle 100 and prevent furtherwork at that job site. With the work complete at job site 154, vehicle100 can be transported from job site 154 to job site 160 on trailer 158,and can then commence work at job site 160. ECU 135, following the samelogic, will monitor location sensor 136 and increment the elapsed enginerunning time timer in the memory 148 of ECU 135. ECU 135 is configuredto periodically compare this elapsed engine running time at job site 160to the 30 hours allotted for that job, which is also stored in memory148. When vehicle 100 has worked for the agreed-upon and programmed 30hours, ECU 135 will shut down engine 112 of vehicle 100.

The foregoing paragraph is just one example. The flexibility of thesystem, however, rests in its ability to simultaneously maintain bothjob site boundaries and associated timers in memory 148 and permitoperation at either job site in any order, and at any time, until thepredetermined allotted time for operation at each particular job sitehas elapsed. For example, and as is often the case at construction worksites, work may be delayed at one job site for sudden and unanticipatedreasons: another contractor may not perform his preparatory work, badweather may prevent vehicle 100 from working outside, or governmentalapprovals may be delayed. Whatever the reason, vehicle 100 can easilyaccommodate these delays by ceasing operations at one job site beforeits total allotted time at that job site has expired, and beginning work(or continuing work) and another job site.

As one illustrative example assume that the operator stops working afterhaving worked only five hours at job site 154. ECU 135 has kept anongoing record of the elapsed engine running time at job site 154, andthus stores data indicative of the time worked (five hours) as well asthe total engine running time permitted at that job site (20 hours).

The operator can then load vehicle 100 onto trailer 158 and move it tojob site 160, the alternative job site where vehicle 100 is also (usingthe example above) programmed to perform 30 hours of work. Upon arrivalat job site 160, vehicle 100 can be started and will operate for up to30 hours within the boundaries of job site 160. ECU 135, determiningthat vehicle 100 is within the boundaries of job site 160, willincrement the timers for work performed at job site 160, and notincrement the timers for work performed at job site 154. As the operatoroperates vehicle 100 at job site 160, ECU 135 periodically monitorslocation sensor 136 and determines that vehicle 100 is operating at jobsite 160. ECU 135 is programmed to increment the timer that indicatesthe elapsed operating time at job site 160. If work at job site 160 isdelayed, after (for example) 10 hours of work has elapsed, the operatorcan load work vehicle 100 back on trailer 158 and return to job site154. When the engine of vehicle 100 is started at job site 154, ECU 135monitors location sensor 136, determines that vehicle 100 is back at theoriginal job site 154, and updates the elapsed engine running time timerfor job site 154. In this example, since five hours of operation havealready elapsed at job site 154, control system 134 now updates theelapsed engine running time timer for job site 154 starting with thepreviously elapsed five hours and permits an additional 15 hours ofengine running time at job site 154 until the total operating time atjob site 154 is consumed, at which time ECU 135 shuts down the engine.

ECU 135 periodically compares the elapsed operating time at each jobsite with the predetermined operating time at that job site. When theelapsed time equals or exceeds the predetermined operating time, ECU 135disables the vehicle 100. This disabling is done on a job-site-byjob-site basis. In other words, vehicle 100 can meet the predeterminedoperating time limit for one job site, and ECU 135 will responsivelydisable the vehicle at that job site, preventing further operation atthat job site. The vehicle will still be capable of operation at otherjob sites for which vehicle 100 has not reached its correspondingoperating time limits.

When and how often vehicle 100 travels back-and-forth between job site154 in job site 160 is at the operator's discretion. Since ECU 135 knowsimmediately what job site it is working at based upon what preprogrammedjob site boundary it is within, based upon the signal from the locationsensor, ECU 135 always knows which job site timing counter should beincremented, and whether the permitted time of operation has beenexceeded.

Programming Boundaries and Operational Times

In the preferred configuration, control system 134 stores both theboundaries and the operational time associated with each boundary aswell as the various timers that are incremented in the memory of ECU135. ECU 135 is configured to store not just two job sites and job siteboundaries and associated timers, as illustrated herein, but as many jobsites as can be contained in the memory of ECU 135.

Maintaining all jobsite information in the memory of the vehicle's ECUpermits vehicle 100 to operate independently of any centralized fleetmanagement system—at least until the various time limits are exceededand the vehicle is ultimately disabled. In the process described in TimeLogging, above, ECU 135 determines that the vehicle is or is not withina boundary and has or has not consumed its hours at each job site byexamining the location provided by location sensor 136 and comparing itwith the boundaries and the permitted maximum number of hours ofpresence, running, or operating for that job site, which are stored inmemory 148.

These boundaries and operational times can be programmed using any of(1) the long-range wireless communications circuit 138, (2) theshort-range wireless communications circuit 140, and (3) the wiredcomputer communications circuit 142. ECU 135 is programmed tocommunicate with another computer having the jobsite boundary andjobsite maximum time data by any one of these links.

In one configuration, the operator can bring a portable computer device143 (FIG. 2) with a short-range wireless connection such as an 802.11xor Bluetooth transceiver in close proximity to the vehicle and cantransmit the boundary and operational time data for one or more jobsites directly from the handheld computer device to ECU 135 via shortrange circuit 140.

In another configuration, the operator, using a remote computer device143 (FIG. 2) with a cellular phone or satellite phone connection, candial the corresponding cellular phone or satellite phone circuit of thelong-range wireless communications circuit 138 and transmit the boundaryand operational time data for one or more job sites to ECU 135.

In yet another configuration, the operator can go to vehicle 100 andmake a wired connection between a portable computer device 143 and wiredcommunication circuit 142 of ECU 135. Once this connection is made, theoperator can transmit the boundary and operational time data to ECU 135.

The description above is provided to illustrate particularly preferredembodiments of the invention. What is new, however, and what isprotected by the claims below is not limited to the particular machinesand processes described above. The invention may cover more than theparticular machines and methods described above. The claims below areintended to communicate the actual scope of the invention and what isprotected from infringement.

Certain modifications can be made to the machines and processes abovewhile still falling within the scope of the claims below.

1. An access control system for a work vehicle having an engine and alocation, the system comprising: a location sensor on the vehicle, thesensor configured to provide a location signal indicative of thevehicle's location; and an electronic control unit coupled to thelocation sensor to receive the location signal, the electronic controlunit further comprising an electronic memory configured to store dataindicative of a plurality of non-contiguous job sites, and furtherwherein the electronic control unit is configured to permit operation ofthe vehicle within the non-contiguous job sites and to disable thevehicle when the vehicle leaves the non-contiguous job sites.
 2. Thesystem of claim 1, wherein the electronic control unit is configured toshut down the engine when the vehicle leaves the plurality ofnon-contiguous job sites.
 3. The system of claim 1, wherein theelectronic control unit is configurable to prevent the vehicle frombeing driven between two of the plurality of non-contiguous job sites.4. The system of claim 1, wherein the electronic memory stores aboundary for each of the plurality of non-contiguous job sites. 5-9.(canceled)
 10. The system of claim 4, wherein electronic memory is alsoconfigured to store a first timer associated with the first job site,and to store a second timer associated with the second job site.
 11. Thesystem of claim 1, wherein the location sensor includes a GPS receiver.12. The system of claim 10, wherein the electronic control unit isconfigured to store in the first timer a value indicative of the amountof time the vehicle is located at the first job site, and wherein theelectronic control unit is configured to store in the second timer avalue indicative of the amount of time the vehicle is located at thesecond job site.
 13. The system of claim 10, wherein the electroniccontrol unit is configured to store in the first timer a valueindicative of the engine's running time at the first job site, andwherein the electronic control unit is configured to store in the secondtimer a value indicative of the engine's running time at the second jobsite.
 14. The system of claim 10, wherein the electronic control unit isconfigured to receive a definition of a third job site from a circuitselected from a group comprising a long-range wireless communicationscircuit, a short-range wireless communications circuit, and a wiredcomputer communications circuit.
 15. The system of claim 14, wherein thelong-range wireless communications circuit is a circuit selected from agroup comprising a cellular telephone and a satellite telephone.
 16. Thesystem of claim 14, wherein the short-range wireless communicationscircuit is a circuit selected from a group comprising a Bluetoothcircuit and an 802.11 circuit. 17-18. (canceled)
 19. The system of claim1, wherein the controller is configured for disabling the vehicle suchthat the vehicle is prevented from being driven from one of theplurality of non-contiguous job sites to another of the plurality ofnon-contiguous job sites. 20-22. (canceled)
 23. The system of claim 13,wherein the electronic control unit is also configured to store a firsttotal engine running time and a second total engine running time, and isconfigured to shut down the engine when the first timer exceeds thefirst total engine running time and when the second timer exceeds thesecond total engine running time.
 24. The system of claim 13, whereinthe electronic control unit is configured to store timer valuesindicative of vehicle movement at each job site and disable the vehicleif either value exceeds an associated predetermined vehicle time limitfor vehicle movement at each job site.
 25. The system of claim 13,wherein the electronic control unit is configured to store timer valuesindicative of implement operation at each job site and disable thevehicle if either value exceeds an associated predetermined vehicle timelimit for implement operation at each job site.
 26. The system of claim23, wherein the electronic control unit also includes a timer configuredto store an overall engine running time of the vehicle.